I love Maiden and Priest, won't pick one over the other. I just saw this thread and wanted to pop in to say:

When my son was 3.5yo he was toddling through the music section of Best Buy and just HAD to have The Final Frontier, so I bought it for him. Every day for a year whenever he climbed into his car seat for a ride he'd say, "can we listen to Iron Maiden daddy?"

"Sure, son. Up the irons!"

A few weeks ago I wanted to turn him on to some Priest so I bought a compilation and now he wants to hear that, all the time.

A 6 year old boy's vocal chords are perfect for hitting the high notes on "Exciter".